The second series will feature a brand new story from creator and writer Chris Lang who once again explores the fallout from the investigation into an historic murder case.

The story begins with the discovery of a body. This time the perfectly preserved remains of a middle aged man found in a sealed suitcase in the silt of the River Lea in northeast London. As Cassie and Sunny begin the complicated task of trying to identify the victim, we will meet four unconnected people who we suspect are linked in some way to the victim.

The dead man turns out to be David Walker who disappeared in 1990 and left behind a wife, who has since remarried, and her son who is now in his early 30s. Their story will run across six episodes and will draw upon very current themes and jeopardy.

The drama will continue to explore some of the themes of the first series, but the primary theme will be our society's relationship with evil. When exactly does a good person start becoming defined by society as a bad person, and at what point in their life does a damaged child stop being exempted for their crimes allowing us to simply label them evil.

"We were delighted at the response to Unforgotten and it's fantastic to be bringing back Cassie and Sunny to investigate a different historical murder,” said Sally Haynes on behalf of producers Mainstreet Pictures. “As with the first series Chris has written a complex, emotional and surprising story that challenges our heroes as they uncover long hidden secrets in the lives of the suspects".

Unforgotten writer, creator and Executive Producer Chris Lang said: “I am so excited to be making a second season of Unforgotten. Once again we have managed to assemble a jaw dropping cast, alongside a hugely talented production team, and I cannot wait to see the stories I have created, start to come to life on screen.”